Seth Peterson, who grew up in Amherst, was safely inside his home near the Mattapan and Dorchester line with his wife, Susan, and daughter, Stella, Friday morning.

“It is surreal and, as a parent, very frightening to think of how many people, how many families are linked to this unfolding tragedy,” Peterson said in an email.

Though at the southeastern edge of the city, and likely a safe distance from what he described as the “high impact” and “high stress” areas of Watertown and Cambridge, the massive manhunt with local and state police and National Guard gave the city a different feel.

“The heroism of the first responders is awe-inspiring, but the militarization of our city is profoundly unnerving,” Peterson said.

Since the bombings, those affected by the tragedy have been the focus of his thoughts, he said.

“Given that these suspects attended schools here, worked and lived in the area, given how many people participated in the marathon, everyone has tentacles that connect to these horrific events,” Peterson said. “Those closest to it are suffering such pain, anger and bewilderment.”